While it's not the most full-featured image editor you'll ever use, Pixlr makes it fairly easy to do some sophisticated (and unsophisticated) things with images online. The Flash-based web app has an impressive set of tools, from a text engine that can use nearly any font available on your computer to layers and filters for masking and effects, respectively. Incredibly, there's even a multilevel undo! You can import images from your machine or via URL, or paint something up yourself, and either way save it to your desktop. It's fun to play around with, though quickly frustrating if you're used to more powerful tools. But it sure beats MS Paint! Original photo by Mike G.
Pixlr

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